fix video endslate icon

- Change video endslate icon from dark to white

![image](https://cloud.githubusercontent.com/assets/960919/4370905/9da1e7dc-430f-11e4-9f72-2482893e06b6.png)

![image](https://cloud.githubusercontent.com/assets/960919/4370907/ac9ba35e-430f-11e4-8142-edfcecf82b5a.png)